Fluid operated pump



y c. J. COBERLY 2,242,777

FLUID OPERATED PUMP Filed July 29', 1958 5 Sheets-Sheet 1 /NVNTOR CLARENCE Ll COBL'RLY FOR 7' FIR/1 A r TORNE Y6.

Patented May 20, 1941 FLUID oraas'mn PUMP Clarence J. Coberly, Los Angeles, Calif., asslgnor t ROKo Co p Reno, Nev., a corporation of Nevada Application July 29,1938, Serial Nb. 221,963

6 Claims. (01. 103-5) This invention relates to the well pumping art, and more particularly to an apparatus adapted to pump fluid from a well by the use of a fluid operated pump operating incombination with a gas lift device.

The invention is of particular utility in the oil industry, and, accordingly, will be described in connection with such use, although it is to be understood that the invention has other fields of use andthat I do not intend to be limited by the particular use described.

It is common practice in the oil industry to inject gas under pressure into a column of oil in a well to cause the oil and gas mixture formed thereby to flow to the surface of the ground. Such gas lifts, as they are termed in the industry, are of many well-known types, but in all of them gas under high pressure is injected into the column of oil to be raised, and in many of such gas lifts the gas pressure is directly communicated through the well oil to the producing formation. If, as is common, the well formation pressure causing the oil to flow into the well from the adjacent oil sands is low, the pressure exerted on the formation by gas of such a gas lift will materially decrease or entirely prevent the flow of oil from the formation into the well, and the gas lift will either be impractical or entirely inoperative to raise oil from the well. For example, it frequently occurs that the formation pressure in a well is in the neighborhood of 30 to 40 pounds per square inch, whereas it is common to use gas pressures in the gas lift of about 400 pounds per square inch in a deep well. In such cases, the high gas pressure communicated to the well formation opposes the formation pressure, and the gas lift is inoperative or impracticai to raise oil from the well, In the use of all such gas lifts, therefore, the formation pressure determines the maximum gas pressure that can be employed in the lift, which is frequently much below the maximum gas pressure which would be used if this pressure did not oppose the flow of oil into the well. In other words, such gas lifts are incapable of producing the maximum possible fiow of oil from the well and operate at low eificiency.

It is therefore a primary object of my invention to provide a gas lift device in which no gas pressure is applied to the well formation from the well opposing the formation pressure normally causing oil to flow into the well from the formation. I prefer to accomplish this by providing a packing means for forming a reservoir in the well, a pump for raising oil above the packm means into the reservoir, and a gas lift mechanism for injecting gas into the column of oil above the packing means to raise the oil from the well.

It is a further object of my invention to pro- :vide a gas lift device as described in the preceding paragraph which continuously raises oil from the well. Some types of gas lifts have been designed which operate intermittently, but I desire to avoid the low eificiency characteristic of such devices.

Another object of the invention is to provide a gas lift pumping device incorporating a displacement pump of the reciprocating piston type of low pressure and high volume to raise oil in a well to a point at which gas is injected into the oil to raise the oil to the surface of the ground, the pump operating at a pressure substantially equal to or slightly higher than the pressure of the gas utilized, to prevent back pressure on the well formation. To accomplish this purpose I prefer to employ a fluid operated pump, although it will be understood that other types of such displacement pumps may be substituted therefor without departing from the spirit of my invention.

Still another object of the invention is to provide a fluid operated pump adapted to operate at low pressure to pump continuously a high volume of fluid.

A further object of my invention is to provide a novel type of pumping mechanism for a well.

Another object of the invention is to provide a novel form of packing means for a well casing, which includes means for hydraulically sealing the packing means in engagement with the casing.

A further object of the invention is to provide a novel type of pump piston having means for lubricating the surface thereof during operation.

Other objects and advantages will be apparent from the following description and drawings, in which:

Fig. 1 is a diagrammatic assembly view, partly in section, showing my invention disposed in a well.

Fig. 2is a sectional view of the upper end of my invention.

Fig. 3 is a sectional view of the intermediate portion of my device, being continued downwardly from the lower end of Fig. 2.

Fig. 4 is a sectional view of the lower end of my device, being continued downwardly from the lower end of Fig. 3.

Fig. 5 is a cross-sectional view taken on the line 5-5 of Fig. 2.

Fig. 6 is a cross-sectional view taken on the line 5-6 of Fig. 2.

Fig. 10 is an enlarged sectional view of the lower end of the device shown in Fig. 9.

Fig. 11 is an enlarged sectional view of an alternative form of piston.

Fig. 12 is a fragmentary sectional view taken on the line |2-|2 of Fig. 11.

Referring to Fig. l of the drawings, I show an oil well 26 having the usual type of easing 2| therein secured at its upper end to a casing head 22, as is well knownin the art. Secured at its upper end to the casing head 22 is a string of gas tubing 23 extending downwardly into the well and communicating through the casing head with a gas pipe 24 leading to a gas compressor 25 of any suitable type well known in the art. A gas inlet pipe" conducts gas from a suitable source (not shown) to the gas compressor 25. Extending downwardly within the gas tubing 23 is an operating fluid tubing 21 which passes upwardly through the casing head 22 and is suitably secured thereto, and leads to a high pressure delivery pump 28 adapted to receive suitable operating fluid from a source of supply (not shown) through an inlet pipe 25 and force it under high pressure downwardly through the tubing 21. The high pressure delivery pump 28 may be of any suitable design well known in the art.

As shown in Fig. 2, the lower end of the gas tubing 23 is threadedly connected by a collar to a packing means 3| which is primarily designed to form a fillid- -tight seal between the lower end of the gas tubing and the 'well casing 2|. The packing means 3| is comprised of an upper outer tubular member 32 threaded at its upper end to the collar 36 and threaded at its lower end to a connector plug 33. The connector plug 33 has a threaded central bore 34 into which is'threaded the lower end of an upper inner tubular member 35 which projects upwardly within the outer tubular member 32 and has secured to its upper end a guide element 35 having a flared bellshaped mouth 31. The lower end of the operating fluid tubing 21 is connected through a collar 38 to a tubular fitting 38 having threaded in its lower end an externally tapered tip 40.

As will be described hereinafter, the flared mouth 31, the guide element 35, and the tapered tip 40 of the tubular fitting 39 cooperate to permit the tubular fitting to be inserted readily into the inner tubular member 35.

Secured to the lower end of the connector plug 33, as by threads or otherwise, is a cylindrical member 4| having a bore 42 in which a packer piston 43 makes a close sliding fit. The upper end of the packer piston 43 is provided with a packing cup 44, formed of leather or other resili-' outer end rigidly connected to a packer sleeve 50.

The cylindrical member 4| has an intermediate wall 5| formed integrally therewith which closes the lower endof the bore 42 and forms a lower chamber 52 therein. Bridging the intermediate wall 5| are vertical passages 53 formed in the cylindrical member 4| which communicate between the lower chamber 52 and a space 54 formed between the upper end of the cylindrical member and the connector plug 33, as shown in Figs. 5 and 6. Externally threaded to the lower 1 end or the cylindrical member 4| is a collar 55 which is in turn threaded to the upper end of an intermediate production tube 56, and internally threaded to the cylindrical member is an inwardly flared collar 51 which is in turn threadedly connected to the upper end of an intermediate pressure pipe 58.

The intermediate production tube 55 is externally upset, as shown at in Fig. 3, on which is secured a flange ring 5| on which rests a packer element 52 comprised of upper and lower clamp rings 53 and 54, respectively, between which is clamped a tubular packing formed of rubber or other suitable material. The upper clamp ring 53 is adapted to slide on the intermediate roduction tube 56, and the upper end thereof is engaged by the lower end of the packer sleeve 55. Registering openings and 51 are provided in the packer sleeve 50 and the intermediate production tube 55, respectively.

The lower end of the intermediate pressure pipe 58 is connected to a fluid operated motor 10 shown in detail in Figs. 9 and 10. Fluid operated motors are old in the art, and no claim is made herein to the specific construction shown of my invention. In general, the fluid operated motor 10 includes a valve body 1| suitably attached to the upper end of a motor cylinder member 12, suitable passages 13 and 14 being formed therein to conduct operating fluid to opposite ends of the motor cylinder member. A master valve member 15 is provided in the valve body 1| to alternately open communication between the passages 13. and 14 and the intermediate pressure pipe 58, and pilot valve mechanism 15 is provided to cooperate with the upper end of an upper piston rod 11 to control the operation of the master valve member. The upper piston rod 11 extends downwardly into the motor cylinder member 12 and has connected to its lower end a motor piston 18 adapted to reciprocate in the motor cylinder member, the upper 'piston rod having a longitudinal passage 19 therethrough which is at all times in communication at its upper end with the intermediate pressure pipe 58.

Secured to the lower end of the intermediate production tube 55 is a pump mechanism 85, shown in detail in Figs. 3 and 4, which is adapted to pump well fluid from the lower end of the casing 2| upwardly to a point above the packing means 3|. The pump mechanism includes an upper inlet member 85 threadedly secured to the intermediate production tube 56 in which a plug member 81 of the fluid operated motor 10 is threaded. The upper inlet member 85 has threaded theretoa pump cylinder member 88, to the lower end of which is threadedly secured a lower inlet member 89, as shown in Fig. 4. Threaded to the lower inlet memger 89 is a lower tubular element 80 having its lower end closed by a suitable plug 9I'.

The upper inlet member 86 is provided with upper inlet passages 92 which communicate between the exterior of the upper inlet member and a pump bore 93 of the pump cylinder member 88, which passages provide means for ingress of well :fluid into the upper end of the bore 93. Also formed in the upper inlet member 86 are vertical passages 94 which provide open communication between the upper end of the pump bore 93 and the lower end of the intermediate production tube 56. Check valve means 96 are provided at the upper end of the pump bore 93 to control the inlet and discharge of well fluid into and out of the upper end of the pump bore. The check valve means 96 is comprised of a valve seat member 91 which rests on a cylinder liner 98 provided in the pump cylinder member 88, the valve seat member having an external diameter smaller than the internal diameter of the pump cylinder member so as to provide an annular space 99 therebetween, and having discharge passages I formed therein which communicate between the upper end of the pump .bore 93 and the space 94a. An annular discharge valve element IN is provided to move vertically on a. tubular extension I02 formed on the upper inlet member 86 and is normally held by a spring I03 so as to close the discharge passages I00. charge check valve which permits fluid to discharge from the pump bore 93 through the space 94a and the vertical passages 94 into the intermediate production tube 56, but prevent a reverse flow of fluid. The valve seat member 9'! is also provided with inlet passages I04 which communicate between the upper inlet passages 92 of the upper inlet member 86 and the pump bore 93. Threaded into the tubular extension I02 of the upper inlet member 86 is a plug element I04a which assists in clamping the valve seat member 9! to the upper inlet member, and on which is positioned an annular inlet valve member I05 which is normally held by a compression spring I06 in engagement with the valve seat member 91 so as to close the inlet passages I04, to prevent fluid from passing from the upper end of the pump bore 93 outwardly through the upper inlet passages 92, but permitting the reverse flow of fluid from the well.

Threadedly connected to the lower end of the motor piston I8 is an intermediate piston rod H0 having a longitudinal passage III therethrough, suitable packing H2. being provided between the intermediate piston rod and the plug member 81 to prevent leakage of 'fluid therebetween. The intermediate piston rod H0 is extended downwardly through a suitable bore in the upper inlet member 86 and through the plug element I04a, and is threaded at its lower endto a pump piston H3, as shown in Fig. 4. The pump piston H3 may be of any suitable type, but Iprefer to construct this pump piston with a central body I I5 having a bore H6 and having formed thereon an annular flange H'I against which are positioned upper and lower packing cups H8 and H9, respectively, which hold upper and lower packings I and I2I, respectively, made of rubber or other resilient material, the same being held in position by upper These elements forman upper dis-.

and lower follower cups I22 and I23, respectively, which are threaded on the central. body H5. The packings I20 and I2I prevent leakage of fluid past the pump-piston I i The lower inlet member 89 is threadedly secured to the pump cylinder member 88 and is formed to control the flow of well fluid into and out of the lower end of the pump bore 93 below the piston H3, being generally similar in construction and function to the'upper inlet member 86. The lower inlet member 89 is provided with lower inlet passages I25 which communicate between the pump bore 93 and the exterior of the lower inlet member, the upperends thereof being closed by an inlet check valve member I26, similar in construction to the annular inlet valve member I05, and adapted to permit well fluid to flow through the lower inlet passages into the pump bore but constructed so as to prevent a reverse flow thereof. A lower valve seat member I2! is also provided, being in all respects similar to the valve seat member 91 and being provided with lower discharge passages I28 closed by a lower discharge valve element I29 similar to the discharge valve element IOI, to permit fluid to flow from the pump bore 93 through the passages I28 into a lower annular space I30 communicating directly with the lower end of liner passages I3I formed in the cylinder liner 98.

'I'hreadedly secured in the bore I I6 of the pump piston I I3 is a lower piston rod I 32 which extends downwardly through the lower inlet member 89, having suitable packing I33 therebetween to prevent leakage, and. extends into a lower tubular member I34 threadedly secured to the lower inlet member and having its lower end closed. The lower piston rod I32 is provided with an axial passage I35 which passes from end to end thereof and communicates with the central bore H6 of the pump piston H3.

When installing my device in a well, the parts thereof are assembled substantially as shown in Figs. 2, 3, and 4, at which time the transverse arm 48 of the packing means 3I is in its uppermost position, and the device is lowered into position in the well 20 suspended fromthe lower end of the gas tubing 23. The operating fluid tubing 2! may or may not be run into the well in assembled position, and it will generally be found preferable to lower the gas tubing 23 to working position before the operating fluid tubing islowered into the well. The flared bell-shaped mouth 31 formed on the guide element 36 is specifically provided so as to guide the externally tapered tip 40 of the tubular fitting 39 securedto the" lower end of the operating fluid tubing 21 into the position shown in Fig. 2. 'When the device and its parts are in the positions shown, the high pressure delivery pump 28 is actuated to re ceive pressure fluid such as oil, from a suitable source of supply (not shown) through the inlet'pipe 29 and to convey it under high pressure through the operating fluid tubing 21 downwardly therethrough to the fluid operated motor 10. As soon as fluid pressure in the operating fluid tubing 21 is exerted on the packer piston 43 and its parts, this pressure causes the packer piston to move downwardly in the bore 42, thus moving downwardly the transverse arm 48 and the packer sleeve 50 connected thereto. Since the lower end of the packer sleeve 50 engages the upper clamp ring 63 of the packer element 62, downward movement of the sleeve presses the tubular packing 65 between the upper and lower clamp rings 63 and 64, causing the ated. It will be understood that as soon as pressure is released on the column of pressure fluid in the operating fluid tubing 21, the natural resiliency of the tubular packing 55 will operate to force the upper clamp ring 53 and the packer sleeve 50 in engagement therewith upwardly so as to permit withdrawal of the packing means 3i from the well casing 2I.

High pressure operating fluid fills the space 54 and freely flows therefrom downwardly through the vertical passages 53 into the lower chamber 52 of the cylindrical member H, from whence it passes through the inwardly flared collar 51 into the intermediate pressure pipe 58, passing therefrom through a screen strainer member I40 directly into the upper end of the fluid operated motor 10. As indicated above, the fluid operated motor I is of a type well known in the art, the high pressure fluid flowing alternatively through the passages I3 and I4, as controlled by the position of the master valve member I5, into the upper and lower ends of the motor cylinder 12a, to reciprocate the motor piston 18 therein. Reciprocation of the motor piston 18 reciprocates the upper piston rod 'I'I to actuate the pilot valve mechanism I controlling the operation of the master valve I5, and reciprocates the intermediate piston rod IIO which has connected at its lower end the pump piston III. It is to be noted that the high pressure fluid from the intermediate pressure pipe 58 has direct access at all times through the longitudinal passage 19 of theupper piston rod, the motor piston 18, the longitudinal passage II I of the intermediate piston rod IIO, the bore II5 of the pump piston H3, and the axial passage I35 of the lower piston rod I32 to a space I at the bottom of the lower tubular member I34. It will thus be understood that the pressure on the upper and lower ends of the piston rods are balanced, which feature is fully covered in my Patent No. 2,081,220,

issued May 25, 1937, and that high pressure fluid is free to flow through the piston rod at all times.

Reciprocation of the pump piston H3 causes it to pump fluid from the well casing 2I. When the pump piston H3 is raised from the position shown in Fig. 4, any fluid thereabove will discharge through the discharge passages I00 of the valve seat member 81 into the space 84a from which it is forced upwardly through the vertical passages 94 into the lower end of the intermediate production tube 56 and thence upwardly therethrough. As the pump piston II3 rises in the pump bore 93, a suction is created below the pump piston which opens the lower inlet check valve member I20 against the action of its spring to draw fluid into the lower end of the pump bore from the well casing 2I through the lower inlet passages I25.

When the pump piston II3 moves downwardly in the pump bore 83, upon reversal of its stroke, the lower inlet check valve member I closes in response to pressure thereon, and the lower discharge valve element I29 opens to permit fluid to flow from the lower end of the pump bore 93 into the lower annular space I00, and thence upwardly through the liner passages III into the space 042. where it mingles with the oil discharged from .the upper end of the pump cylinder, and flows therefrom upwardly through the vertical passages 84 into the intermediate production tube 56. Downward movement of the pump piston H8 permits the discharge valve element IN to close in response to the action of the spring I03, and suction is set up in the upper end of the pump bore 03 which opens the inlet valve member I05 to draw well fluid into the upper end of the pump bore through the upper inlet passages 02 and the inlet passages I04 of the upper valve seat member 81. Thus, continued' reciprocation of the pump piston II3 provides a steady flow of well fluid discharging from alternate ends of the pump bore, and causes the same to rise upwardly through the intermediate production tube 55 from whence it passes out- .wardly through the registering openings 61 and 60 into a reservoir space I42 formed by the packer element 82 and the well casing 2|, the well fluid flowing upwardly therefrom driectly through the well casing to a point above the collar 30. Those skilled in the art will understand, from the present disclosure, that although I prefer to use the fluid operated motor I0, or a similar type of motor, to actuate the pump mechanism 85, I do not intend to be limited to the use of such a fluid operated motor for this purpose, and that any other suitable means may be employed to reciprocate the pump piston I I3, such as, for example, sucker rods which are well known in the art, without departing from my invention.

A suitable gas or, other fluid, such as air, is drawn from a suitable source of supply through the gas inlet pipe 25 by the gas compressor 25, in which the gas is compressed to a suitable operating pressure and conducted through the gas pipe 24 and the casing head 22 to the gas tubing 23, in which it passes downwardly therethrough to the collar 30, passing outwardly therefrom through the gas discharge openings 30a to mix with the column of well fluid confined thereabove in the reservoir space I42 of the packing means 3|.

As is well known in the art,-such gas forms bubbles in the column of well fluid confined in the reservoir space I42, which reduce the average specific gravity of the well fluid and gas mixture thus formed to a sufllcient degree to cause the mixture to flow upwardly through the casing 2I to the surface of the ground, where it discharges through the discharge pipe 28a;

It will therefore be understood that the gas pressure employed in lifting the well fluid through the casing is not applied directly to the well formation, but is merely imposed on the column of well fluid in the reservoir space I42, and that the pressure under which the fluid operated pump mechanism 85 delivers well fluid to the reservoir space I42 need only be suflicient to offset the gas pressure employed. Thus, for example, if a gas pressure of 400 pounds per square inch is required to lift the column of well fluid from the reservoir space I42 to the discharge pipe 28a, the pump mechanism 85 may be designed and operated to pump a high volume of well fluid at a pressure of only approximately 400 pounds per square inch, or slightly higher, from the well into the reservoir space I42. It will also be understood that whereas fluid op-'- erated pumps heretofore employed in deep well pumping have been designed to pump a low volume of well fluid at a high pressure, my present fluid operated pump is designed to pump a high volume at low pressure, a function impossible in prior pumps of the. fluid operated type.

In Figs. 11 and 12, I show an alternative form of pump piston I50 which it may be desirable to use in place of the pump piston II3 shown in Fig. 4. The pump piston I50 has a cylindrical body I5I, adapted to make a sliding fit in the pump bore 93 of the cylinder liner 98, the exterior thereof being provided with annular channels I52 receiving piston rings I53 as is well known in the art. The cylindrical body I5I has an upper central bore I54 threadedly receiving the lower end of the intermediate piston rod I I0, and has a lower central bore I55 threadedly receiving the upper end of the lower piston rod I32, the ends of the rods being spaced apart by a chamber I56. Ofiset from the axis of the cylindrical body I5I is a valve cylinder I51 which is closed at its lower end by a lower plug I58 and has at its upper end an upper plug I59 provided with a passage I60 therethrough. slidably disposed in the valve cylinder I51 is a regulator valve member I6I having a cup-shaped piston I62 within which a compression spring I63 is disposed so as to engage both the piston and the upper plug I53, and the valve member is provided with a transverse opening I64 which registers with a port I65 communicating between the interior of the valve cylinder I51 and the exterior of the cylindrical body I5I. The cylindrical body I5I is provided with a transverse openin I66 into which is threaded a transverse pin I61 having a vertical fluid passage I68 communicating with a longitudinal fluid passage I69, one end of the transverse pin projecting into the transverse opening I64 of the valve member I6I and having threaded thereon a tubular cap I10 having a valve orifice I1I therein. Secured to the valve member I6I and projecting upwardly in the transverse opening I64 is a conical valve element I12 adapted to seat in the lower end of the valve orifice "I to close it, the valve member being provided with a passage I13.

My piston I50 is designed to permit a flow of operating fluid under relatively high pressure to the sliding surfaces of the piston and the liner 98 to lubricate them and to prevent foreign materials from lodging therebetween, which is broadly covered in my Patent No. 2,081,220, issued May 25, 1937, the present construction being an improvement thereon. In a deep well installation. such as, for example, a well 6500 feet deep, the pressure of the operating fluid may be as high as 4000 pounds per square inch, whereas in using my present pump the fluid load on the pump piston I50 may only be 400 pounds per square inch. Obviously, if operating fluid under a high pressure, such as 4000 pounds per square inch, is conveyed to the outer surface of the piston, it will either cause excessive leakage lengthwise of the piston or will require an excessive functional duty to be imposed on the piston rings I53. Consequently, the principal object of my piston design shown in Figs. 11 and 12 is to provide a pressure reducing means for reducing the pressure of the operating fluid to a value approximating the fluid load on the pump pisto I50.

In operation. operating fluid under pressure is at all times in the longitudinal passage III of the intermediate piston rod H0 and in the axial passage I35 of the lower piston rod I32, communication therebctween being ail'orded' through the chamber I56 of the pump piston I50. The operating fluid flows through the vertical and longitudinal fluid passages I60 and I69, through the tubular cap I10, and through the orifice I1I into the transverse opening I64. The spring I63 normally exerts a downward force on the valve member I6I tending to hold it in open position in which the valve element I12 is out of seating engagement with the valve orifice I1I. Operating fluid then passes through the passage I 13 into the lower end of the valve cylinder I51, and exerts an upward force on 'the valve member I6I tending to move the valve member upwardly against the action of the spring I63, and any fluid pressure in [the valve cylinder I51 in excess of that required to balance the spring I63 causes the valve member I6I to move upwardly tending to close the valve element I12 in the orifice III. The spring I63 is selected to balance a counter fluid force slightly greater than the maximum fluid load on the piston I50. For example, if the maximum fluid pumping load on the piston I60 is approximately 400 pounds per square inch,

the spring I63 is set to resist movement of the valve member I6I until the pressure of the operating fluid rises above a predetermined maximum, such as 500 pounds per square inch. Thus, if the normal pressure on the operating fluid is 4000 pounds per square inch, the excess pressure in the valve cylinder I51 below the .valve member will move the valve member I 6| upwardly until the valve element I12 is suificiently closed so that the spring I63 will balance the pressure of the fluid in the valve cylinder. It will thus be understood that this construction operates as a regulator to maintain the pressure of operating fluid flowing outwardly through the transverse opening I64 and the port I65 below a predetermined maximum, thus preventing excessive leakage of operating fluid lengthwise of the piston I50, and permitting the use of relatively light frictional contact of the piston rings I53 with the bore 93 of the liner 98. It will also be understood that this piston construction may be used to advantage in other devices, and I do not intend to be limited to its use in connection with a fluid operated pump.

Although I have herein shown and described a simple and practical embodiment of my invention, I do not intend to be limited to the details of construction disclosed but intend my invention to "be accorded the full scope of the following claims.

I claim as my invention:

1. In a deep well pumping device, the combination of: a high-volume low-pressure fluid operated pump in the lower part of a well; operating fluid tubing extending downwardly in said well and communicating with said pump; production Itubing extending downwardly through said well and communicating with said pump; gas tubing extending downwardly through said well and having a port at its lower end communicating with said production tubing at a point adjacent said pump; means for supplying operating fluid through said operating fluid tubing to said pump to actuate said pump to pump a relatively high voliune of well fluid at a relatively low pressure from said well into said production tubing to a level above said port; and means for supplying gas under pressure through said gas tubing and said port into said well fluid in said production tubing to raise said well fluid through said production tubing to the upper end thereof.

2. In a device for use in connection with a well fluid discharged by said pump to the surface of the ground, the combination of: packing means adapted to form a fluid-tight seal between the pump and .the production tubing; a piston having one face thereof in communication with the operating fluid in said supply tubing, said operating fluid being at all times in open communication with said pump through said supply tubing; and means connecting said piston to said packing means so that movement of said piston in response to fluid pressure of said operating fluid expands said packing means to form said seal. i

3. In a deep well pumping device, the combination of: a production tubing extending downwardly in a well; a fluid operated pump in the lower part of the well and adapted to pump fluid from said well into said production tubing; a gas tubing extending downwardly within said production tubing and having a port at its lower end communicating with said production tubing at a point adjacent said pump; an operating fluid tubing extending downwardly within said gas tubing and communicating with said pump; means for supplying operating fluid through said operating fluid tubing to said pump to actuate said pump to pump fluid from said well into said production tubing; and means for supplying gas under pressure through said gas; tubing and said port into said well fluid in said production tubing to raise said well fluid through said production tubing to the upper end thereof.

4. In a deep well pumping device, the combination of: a production tubing extending downwardly in a well; a fluid operated pump in the lower part of the well and adapted to pump well fluid from said well into the lower end of said production tubing, said pump including a motor cylinder therein, a pump cylinder of substantially greater diameter than said motor cylinder having a pump piston therein, piston rod means connecting said pistons, and fluid means for reciprocating said motor piston to reciprocate said pump piston so as to cause said pump to discharge a relatively high volume of well fluid into said production tubing at a pressure insufllcient to raise said well fluid through said production tubing to the upper end thereof; a gas tubing extending downwardly within said production tubing and having a port at its lower end communicating with said production tubing at a point adjacent said pump; an operating fluid tubing extending downwardly within said gas tubing and communicating with said pump; means for supplying operating fluid through said operating fluid tubing to said pump to actuate said pump to pump fluid from said well into said production tubing; and means for supplying gas under pressure through said gas tubing and said port into said well fluid in said production tubing to raise said well fluid through said production tubing to the upper end thereof.

' 5. In a deep well pumping device, the combination of: a production tubing in a well; a fluid operated pump in the well and adapted to discharge well fluid into the lower end of the production tubing; an operating fluid tubing extending downwardly within said production tubing and at all times in open communication with said pump to supply the same with operating fluid under relatively high pressure; packingmeans adapted to form a fluid-tight seal between said pump and said production tubing; a piston having one face thereof in communication with said operating fluid in said operating fluid tubing; and means connecting said piston to said packing means so that movement of said piston in response to fluid pressure of said operating fluid expands said packing means to form said seal.

6. In a deep well pumping device, the combition of: a production tubing in a well; a fluid operated pump in the well and adapted to discharge well fluid into the lower end of the production tubing; an operating fluid tubing extending downwardly within said production tubing and at all times in open communication with said pump to supply the same with operating fluid under relatively high pressure; packing means adapted to form a fluid-tight seal between said pump and said production tubing; a piston having one face thereof in communication with said operating fluid in said operating fluid tubing; and means connecting said piston to said packing means so that movement of said piston in response to fluid pressure of said operating fluid expands said packing means to form said seal, the release of fluid pressure on said operating fluid permitting said packing means to contract to break said seal.

CLARENCE J. COBERLY. 

